1. Field of the Invention
This invention relates to a cable lock for a variety of uses. In particular, this invention relates to a cable lock that allows for insertion but not removal of the cable.
2. The Prior Art
Cable locks are used for a variety of purposes, One use is to lock a device such as a cargo container or a water or electric meter closed. The cable is threaded through the container or meter and then locked in place with a cable lock that cannot release the cable without breaking the lock or cable. This arrangement prevents tampering with the meters, because tampering is easily detected by the presence of a broken or damaged cable or lock.
A cable lock of this type is shown in U.S. Pat. No. 5,611,583 to Bystry et al. This cable lock has a locking mechanism comprised of a spring-loaded disc that is pressed against the cable and prevents backward movement of the cable once it is inserted into the lock. A similar device is shown in U.S. Pat. No. 5,647,620 to Kuenzel, which also uses a spring-loaded disc to prevent release of the cable from the lock. U.S. Pat. No. 3,770,307 to Van Gompel and U.S. Pat. No. 4,049,303 to Irwin et al. also show a disc as the locking mechanism.
U.S. Pat. No. 3,994,521 to Van Gompel discloses a cable lock in which the locking means comprises two spring-loaded ball bearings, which press against the cable to hold it in place. U.S. Pat. No. 5,092,641 to Penick, Jr. discloses another cable lock in which the cable is held in place by a round hasp that is pressed against the cable by a flexible O-ring. U.S. Pat. No. 4,747,631 to Loynes et al. discloses a cable lock that also uses a round hasp to lock the cable in place. In this patent, the hasp is held in place by a leaf spring and a toothed inclined ramp.
Other cable locks and locking devices are shown in U.S. Pat. No. 3,017,678 to Christensen, U.S. Pat. No. 3,744,098 to Bowers, U.S. Pat. No. 1,660,040 to Lehtonen, U.S. Pat. No. 1,139,595 to Starr, and U.S. Pat. No. 2,544,086 to Herrington.
While all of these devices serve to lock cables in place, many of them can be tampered with and released with careful maneuvering of the cables.